topic Re: mirror root in Operating System - HP-UX

mirror root

Nobody's Hero — Mon, 29 Aug 2005 14:36:26 GMT

Trying to mirror root after an 11.11 upgrade. The upgrade wipes out the mirror.

Here is what I get:

#vgextend /dev/vg00 /dev/dsk/c2t6d0
vgextend: Couldn't query volume group "/dev/vg00".
Possible error in the Volume Group minor number; Please check and make sure the group minor number is unique.

Re: mirror root

Gary L. Paveza, Jr. — Mon, 29 Aug 2005 14:41:10 GMT

I had a problem similar to this this past weekend. Looked like the kernel was out of sync with the volume groups. A reboot cleared it up nicely.

Of course first check to see that you infact do not have duplicate minor numbers:

ls -la /dev/vg*/group

Check the 0x number. The first two digits after the 0x are the minor numbers. They should be unique.

Re: mirror root

Nobody's Hero — Mon, 29 Aug 2005 14:42:42 GMT

Oh yea, I can't even to a vgdisplay....not good.

vgdisplay -v /dev/vg00
vgdisplay: Couldn't query volume group "/dev/vg00".
Possible error in the Volume Group minor number; Please check and make sure the group minor number is unique.
vgdisplay: Cannot display volume group "/dev/vg00".

Re: mirror root

Torsten. — Mon, 29 Aug 2005 14:42:55 GMT

Hi Robert,

was this disk in use befor or is it already a physical volume? Check your /etc/lvmtab and vgdisplay output file if the disk is included, if not, create it as a physical volume first
pvcreate (-f) -B /dev/rdsk/c2t6d0,
then vgextend.

You will get a lot of response with advisories how to mirror the disk, I'm sure
;-))

Re: mirror root

Nobody's Hero — Mon, 29 Aug 2005 14:43:39 GMT

Here is what I get...looks ok to me...

ls -al /dev/vg*/group
crw-r----- 1 root sys 64 0x000000 Aug 20 13:13 /dev/vg00/group
crw-r--r-- 1 root sys 64 0x030000 Nov 10 2004 /dev/vg01/group
crw-r--r-- 1 root sys 64 0x040000 Nov 10 2004 /dev/vg02/group
crw-rw-rw- 1 root sys 64 0x010000 Aug 20 16:57 /dev/vgfinap/group
crw-rw-rw- 1 root sys 64 0x020000 Aug 20 17:23 /dev/vgfindb/group

Re: mirror root

Nobody's Hero — Mon, 29 Aug 2005 14:45:08 GMT

This was a new disk I installed for the mirror. It was probably used before.

I tried to do a pvcreate -f on it, but no luck. Says its already in the lvmtab...and it is.

Re: mirror root

Mel Burslan — Mon, 29 Aug 2005 14:45:10 GMT

I have not done a "upgrade" per se to 11.11 but if I my memory serves me right, there was an issue about this while upgrading. The mirror copy does not get preserved as if you are recovering from an ignite image.

something you can try :

mv /etc/lvmtab /etc/lvmtab.old
vgscan -a

Re: mirror root

Nobody's Hero — Mon, 29 Aug 2005 14:49:59 GMT

moving the lvmtab and doing a vgscan didn't work...

Re: mirror root

Steven E. Protter — Mon, 29 Aug 2005 14:50:36 GMT

Upgrade should not do that.

Do you have mirror/ux codewords for 11i, you eventually will need them, but existing mirrors should not be touched.

You seem to have an LVM problem and may need to vgexport all of the volume groups, recreate the group files and then vgimport them all.

Back them up first and then do that, re-creating all the minor numberes and everything should be fine.

SEP

Re: mirror root

Juan M Leon — Mon, 29 Aug 2005 14:51:10 GMT

If the reboot does not fix the problem, I will check vgdisplay see if the system thinks that the volume group has a mirror if it does then I will try
vgscan and vgcfgrestore

I hope it helps

Re: mirror root

Torsten. — Mon, 29 Aug 2005 14:51:13 GMT

Please wait and DON'T pvscan so fast!!!
We could/should do some checks before.

Re: mirror root

James R. Ferguson — Mon, 29 Aug 2005 15:00:57 GMT

Hi Robert:

If you had MC/ServiceGuard on this system at one time, look for '/dev/slvmvg'. If you find it, do:

# rm /dev/slvmvg
# mv /etc/lvmtab /etc/lvmtab.old
# vgscan -v

...and make sure that any pvlinks are ordered in the primary/secondary arrangemetns you want, since 'vgscan' is likely to change the how you want to declare them!

Regards!

...JRF...

Re: mirror root

Nobody's Hero — Mon, 29 Aug 2005 15:17:01 GMT

No service guard...

Re: mirror root

Tim Nelson — Mon, 29 Aug 2005 15:32:06 GMT

So vgdisplay fails, pvcreate on new disk for mirror fails. How is the OS up and running ?

bdf |grep vg00

anything mounted or are we in kernel boot i.e. /dev/vgroot

single root disk and quorum missing ?

reboot and override quorum hpux -lq

check logs from upgrade.

do vgscan in preview mode

Re: mirror root

Uday_S_Ankolekar — Mon, 29 Aug 2005 16:11:09 GMT

If you have /dev/slvmvg then move this file in to different place and also move /etc/lvmtab file , then run vgscan to recreate lvmtab.

IF this server has ServiceGaurd previously installed then slvmvg file remains in /dev

Re: mirror root

Geoff Wild — Mon, 29 Aug 2005 17:52:04 GMT

strings /etc/lvmtab

where is it? in vg00?

Try reducing it:

vgreduce /dev/vg00 /dev/dsk/c2t6d0

Then try the pvcreate.

I think the disk was in another system - and it was vg00 already - that's why the "minor number" error....

Rgds...Geoff

Re: mirror root

Sameer_Nirmal — Mon, 29 Aug 2005 23:29:23 GMT

The error shows that the vg00 could not be queried because there is no PVs underneath to query whoes should be the part of the vg00 to able to show VG details (vgdisplay)

It is clear that even if you have group file for vg00, it is not pointing to either of the disks. It's quite weired and it is not LVM stuff at all. Are you sure the OS disk is a part of LVM or just a partioned disk?
Since you have the group files there , it doesn't mean the disk is a LVM disk. Or those disk might be used in other system before .

Can you do post the following
pvdisplay -v of the existing OS disk strings /etc/lvmtab

It seems that originally two disks were mirrored with old OE. You might have removed the alt path mirrored disk by reducing the lvs , but you didn't do vgreduce. Thats whay the disk is there in lvmtab. Try vgreduce vg00 /dev/dsk/c2t6d0

Let us know the exact step you had followed during upgrade to know the cause of the problem.

Re: mirror root

vinod_25 — Tue, 30 Aug 2005 05:13:14 GMT

Hi Bob

The problem that you are facing is due to the VGID of VG00 on /etc/lvmtab and on the disk are different.

You can check this by executing the following steps :

[Test-Server]/ >xd -j8200 -N16 /dev/rdsk/cXtXdX
0000000 bfa5 2f7a 430c 4c4c bfa5 2f7a 430c 4c4c

[Test-Server]/ >strings -t d /etc/lvmtab | grep /dev | grep -v /dev/dsk | while read offsetpath; do xd -An -j$(($offset+1024)) -N8 -tx /etc/lvmtab | read vgid1 vgid2;echo $path $vgid1/$vgid2; done
/dev/vg00 bfa52f7a/430c4c4c

compare the disk id and strings output from these commands... if they are different, then you will get the same error.

To Rectify:

# mv /etc/lvmtab /etc/lvmtab.save

# vgscan -v

# vgchange -a y vg00

# vgdisplay vg00

Your problem will be solved...

All the best

Vinod